Weak Assertives and Faultless Disagreement Over Vague Predicates

One of the challenges that any theorist of vagueness faces is to account for there being two kinds of disagreement over vague predicates like “tall” and “rich”: canonical disagreements concerning clear cases and faultless disagreements concerning borderline cases. I’ll argue that one needs to maintain that the illocutionary force of borderline utterances is different from that of clear utterances. Whereas the latter might be correct assertions, the former should be assertives weaker than assertions, since they express only a weak belief of the speaker. The degree of commitment to the truth of what is said in a borderline utterance is lower and neither speaker of two opposing verdicts makes a mistake.